Plant Molecular Biology

, 69:383

Hormone interactions at the root apical meristem



Plants exhibit an amazing developmental flexibility. Plant embryogenesis results in the establishment of a simple apical–basal axis represented by apical shoot and basal root meristems. Later, during postembryonic growth, shaping of the plant body continues by the formation and activation of numerous adjacent meristems that give rise to lateral shoot branches, leaves, flowers, or lateral roots. This developmental plasticity reflects an important feature of the plant’s life strategy based on the rapid reaction to different environmental stimuli, such as temperature fluctuations, availability of nutrients, light or water and response resulting in modulation of developmental programs. Plant hormones are important endogenous factors for the integration of these environmental inputs and regulation of plant development. After a period of studies focused primarily on single hormonal pathways that enabled us to understand the hormone perception and signal transduction mechanisms, it became obvious that the developmental output mediated by a single hormonal pathway is largely modified through a whole network of interactions with other hormonal pathways. In this review, we will summarize recent knowledge on hormonal networks that regulate the development and growth of root with focus on the hormonal interactions that shape the root apical meristem.


Root meristem Hormonal cross-talk Abscisic acid Auxin Brassinosteroid Cytokinin Ethylene Gibberellin Arabidopsis 


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© Springer Science+Business Media B.V. 2008

Authors and Affiliations

  1. 1.Department of Plant Systems Biology, Flanders Institute for Biotechnology (VIB)Gent UniversityGentBelgium
  2. 2.Laboratory of Molecular Plant Physiology, Department of Functional Genomics and Proteomics, Institute of Experimental BiologyMasaryk UniversityKamenice 5Czech Republic

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